Peripheral rewinding machine for producing rolls of wound web material and corresponding method of winding

ABSTRACT

The rewinding machine comprises: an insertion device ( 11 ) for sequentially inserting winding spindles (M) into a winding area; winding means ( 1, 3, 5 ) in said winding area, which wind predetermined quantities of web material onto said spindles; an extractor ( 25 ) for extracting said spindles from the rolls of web material formed on them; and a recirculation path ( 71 ) for returning the spindles extra from said rolls toward said insertion device. The spindles are made in two portions which can be connected and disconnected; the extractor extracts each of said two portions from a corresponding end of the corresponding wound roll. Means are also provided for reconnecting said two portions to each other so that said spindles can be reinserted into said winding area.

DESCRIPTION

1. Technical Field

The present invention relates to a peripheral rewinding machine forproducing rolls of wound web material, comprising: insertion means forsequentially inserting winding spindles into a winding area; windingmeans, in said winding area, which wind predetermined quantities of webmaterial onto the spindles; extraction means for extracting saidspindles from the rolls of web material formed on them; andrecirculation means for returning the spindles extracted from said rollstoward said insertion means.

The spindles may be caused to rotate by the winding means, or may beinitially made to rotate by suitable members acting on themindependently of the winding means.

The present invention also relates to a method for producing rolls ofweb material, comprising the stages of inserting a winding spindle intoa winding area; winding a predeterminable quantity of web material onsaid winding spindle to form a roll around said winding spindle; andextracting said winding spindle from the roll.

2. Background Art

At the present time, the winding of web material for producing rolls ispreferably carried out by means of rewinding machines of the peripheraltype, in other words those in which the rotary motion for the winding isprovided by members which act peripherally on the roll being formed.Examples of rewinders of this type are described, for example, inGB-A-2105688, U.S. Pat. Nos. 4,487,377, 5,249,756, 5,248,106, 5,137,225,5,368,252, 5,639,046, 5,538,199, WO-A-9421545. These peripheralrewinders are of the continuous and automatic type, in the sense thatthey produce finished rolls in an automatic sequence, causing theinterruption of the web material at the end of each winding operationand thus the formation of a tail edge of the finished roll and a leadingedge of the following roll.

In some rewinding machines of known type, the winding is done on tubularwinding cores or spindles, made from cardboard or similar, which remaininside the roll. In other machines of more recent design, the winding isdone without a tubular winding core, as described for example in U.S.Pat. No. 5,639,046 or in U.S. Pat. No. 5,538,199. With these machines acompact roll without a central hole is produced. This makes it necessaryto use special feeders for the use of the material.

IT-B-1201390 describes a peripheral rewinder in which the rolls areproduced by winding on tubular spindles which are subsequently extractedfrom the formed roll. In this way, each roll has no central tubular corebut has a hole for the insertion of a support typically used in feedersof material in roll form, for example feeders of kitchen paper, toiletpaper or similar. This machine has the disadvantage that the extractionof a relatively long spindle from the roll requires a considerabletractive force to overcome the friction. Furthermore, the sliding of thewhole length of the spindle inside the roll causes deformations of theinner turns of the wound web material.

SUMMARY OF THE INVENTION

The present invention relates to an improvement to peripheral rewindingmachines with extractable winding spindles, of the type described, forexample, in IT-B-1201390.

Essentially, the rewinding machine according to the invention ischaracterized in that the winding spindles are made in two portionswhich can be connected and disconnected; in that the extraction meansextract each of said two portions from a corresponding end of thecorresponding wound roll; and in that means are provided forreconnecting said two portions to each other so that said spindles canbe reinserted into said winding area.

In this way, each portion of spindle has to travel for a shorterdistance inside the roll to be extracted from it. The extraction meansalso have to travel for a shorter distance, and this enables the lateraldimensions to be limited, resulting in a greater ease of laying out theconverting line.

This is particularly important because the present tendency in the fieldof the paper converting industry is to produce parent rolls ofincreasing length, with a consequent increase in the width of therewinding lines. Furthermore, if two portions of spindle, each having alength approximately equal to half the length of the spindle, have to beextracted, this will yield a balancing and a reduction of the stress anda reduction of the deformation of the inner turns of the wound material.

In a possible embodiment of the invention, the extraction means used toextract the winding spindle are associated with two conveyers whichextend laterally with respect to the winding area on both sides, toreturn the two portions of each spindle separately toward said insertionmeans, said means for reconnecting the two portions of said spindles toeach other being located before the winding area. There is no reason whythe two portions of spindle should not be connected before they arereturned toward the insertion area, for example under the extractionarea. In this case, it is possible to provide a single conveyer underthe area of extraction of the two portions of spindle.

In a particularly advantageous embodiment, the conveyers compriserecirculation runways for returning the portions of said spindles, alongwhich the portions of spindle roll by gravity.

The two portions of each spindle can be connected to each other bysnap-fitting or other means. However, in a preferred embodiment, theyhave, at the ends to be connected, complementary conical surfaces whichare used for the axial alignment of the two portions. Their detachmentfrom each other can easily be prevented by positioning lateralcontaining walls along the spindle insertion path. When the winding hasstarted, the two portions of spindle are held together by the turnsbeing wound and by the contact with the winding members.

The method for producing rolls of web material according to theinvention comprises the stages of inserting a winding spindle into awinding area; winding a predeterminable quantity of web material on saidwinding spindle to form a roll around said winding spindle; andextracting said winding spindle from the roll. Characteristically,according to the invention it is provided that said spindle is dividedinto two portions; said two portions are connected before the start ofthe winding of said web material on them; and the two portions ofspindle are extracted separately from the two opposite ends of the rollwound on them.

Further advantageous embodiments of the invention are indicated in theattached claims.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be more clearly understood from the description andthe attached drawing, which shows a practical and non-restrictiveexample of the invention. The drawing shows:

in FIG. 1, a schematic side view of a rewinding machine according to theinvention;

in FIG. 2, a view in the direction II—II in FIG. 1 of a part of themeans of extracting the spindle portions from the finished roll;

in FIG. 3, a local view in the direction III—III in FIG. 1, showing themeans for reconnecting the spindle portions;

in FIG. 4, a detail of the surfaces for connecting together the twospindle portions, in a possible embodiment; and

in FIG. 5, a layout of the machine.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

In the following description, the invention is illustrated in itsapplication to an automatic peripheral rewinder of the type described inWO-A-9421545, but it is to be understood that the same inventive conceptmay also be applied to automatic peripheral rewinders having otherconfigurations.

FIG. 1 shows schematically the winding area of the peripheral rewinder.The letter N indicates a web material to be wound, for example a singleor multiple web of paper, with transverse perforations if required,which is to be wound into rolls. The numbers 1, 3 and 5 indicate threewinding rollers which delimit a winding area in which the rolls R areformed. The web material N is run around the upper winding roller 1 andthe roll R is completed in the area formed among the rollers 1, 3 and 5and in contact with these.

A curved surface 7 which forms an insertion channel for the windingspindles, indicated by M, is located under the winding roller 1. Arotating system 9 which interrupts the web material on completion ofeach individual roll R is located under the curved surface 7.

The winding spindles M are brought toward the insertion area, formedbetween the winding roller 1 and the curved surface 7, by means of aconveyer 11 which collects the individual spindles M from a runway 13.The spindles are brought to the upper area of the conveyer 11 by anintermittent motion and are retained there temporarily by a spring strip15. The insertion into the curved channel formed by the winding roller 1and the curved surface 7 is carried out by means of an insertion device17 rotating about the axis A of the upper terminal wheel of the conveyer11.

The winding systems and the winding spindle insertion systems describedup to this point are essentially identical to those described in greaterdetail in WO-A-9421545, to which reference should be made.

In the initial winding area between the winding roller 1 and the curvedsurface 7 there are located sets of nozzles 19, 21, which, by means ofair jets, start the winding of the free edge of web material generatedby the cutting system 9 around a new winding spindle M inserted into thechannel between the curved surface 7 and the winding roller 1.Alternatively, the winding may be started by wetting the winding spindlewith water or other suitable liquid by one of the known systems, in sucha way as to cause the temporary adhesion of the free edge. There is noreason why use should not be made of other systems for starting thewinding of the free edge of the web material, such as electrostaticcharges, suction spindles, or other equivalent systems.

On completion of the winding, the roll of web material R is dischargedonto a discharge surface 23 and sent toward means indicated in a generalway by 25, which extract the winding spindle from the roll. The windingspindle M is made in two portions, indicated by M1 and M2 in FIG. 4. Thetwo portions are connected together by means of truncated conicalconnecting surfaces indicated by S1 for the portion M1 and by S2 for theportion M2. The surfaces S1 and S2 act only to bring the portions M1 andM2 into a coaxial configuration, a system of locking them together notbeing necessary. It is also possible to provide profiles with frontalengagement which prevent the rotation of the two portions with respectto each other if the first contact with the web material is notsimultaneous and/or uniform in the two portions. For example, it ispossible to provide frontal teeth, shaped in such a way as to cause thetwo portions to be made to rotate simultaneously. The opposite ends ofthe portions M1 and M2 of the winding spindle from the surfaces S1 andS2 have two collars 31, 33 and two heads 35, 37 which enable the twoportions of spindle M1 and M2 to be gripped and extracted, in the waydescribed below, from the formed roll.

The extraction means 25 are double, for the extraction of each portionM1, M2 of the winding spindle M. FIG. 2 shows one of the two means ofextracting one of the two portions M1, M2 of the winding spindle, theother extraction means being symmetrical and being located on theopposite side of the rewinder. For each portion M1, M2 of spindle, theextraction means have a sliding block 41 slidable on guide bars 43 andfixed to a chain or other equivalent endless flexible member indicatedby 45, running around two pulleys 47, 49. Other equivalent mechanismsmay be used for the extraction, for example pneumatic or hydraulicactuators with or without rods. In general, use may be made of anysystem suitable for gripping the projecting end of each portion ofspindle and of extracting it from the roll which has been wound on it.

The number 51 indicates the drive to the endless flexible member 45,which causes an alternating movement of the sliding block 41 as shown bythe double arrow f41. The sliding block carries two guide columns 53 foran extraction member 55 which is movable vertically as shown by thedouble arrow f55 by means of a cylinder and piston actuator 57 carriedby the sliding block 41. The extraction member 55 has a jaw 55A which isused to grip the end of the corresponding portion M1 or M2 of thewinding spindle M at the collar 31 or 33, between the body of theportion of spindle and the head 35 or 37.

In a possible alternative embodiment, a single endless flexible memberof the chain or similar type can act on two sliding blocks 41 located onthe two sides of the machine. In this case, each sliding block is fixedto one of the two parallel sides of the flexible member. The movement ofthe flexible member causes the simultaneous movement in oppositedirections of the two sliding blocks, with consequent simultaneousextraction of the two portions of spindle from the roll, which is notsubjected to stresses which would cause it to make an undesiredtransverse movement.

To carry out the extraction of the two portions M1, M2 of the windingspindle from the formed roll R, the roll is made to roll along thedischarge surface 23 until it is stopped between two side pieces 61,only one of which is visible in FIGS. 1 and 2. The side pieces 61 haveseats 63, open toward the winding area, into which the ends of theportions M1, M2 of the winding spindle M projecting from the roll R areinserted when the roll R is discharged onto the discharge surface 23. Inthis way the roll R is held in a defined position (see FIG. 1 inparticular) by the retaining of the projecting ends of the portions M1,M2 of the winding spindle M.

The side pieces 61 may be adjustable so that they can be matched to theaxial dimension of the rolls R. When the roll R has reached the positionbetween the side pieces 61, the sliding blocks 41 of each of the twoextraction means 25 on the two sides of the rewinder may be positionedadjacent to the side pieces 61 to bring, by a downward movement in thedirection of the arrow f55, the corresponding jaw 55 into engagementwith the corresponding projecting end of the portion M1 or M2 of thespindle. At this point, the sliding block,41 is made to slide along theguides 43 to extract the corresponding portion M1, M2 of spindle untilit is brought into the position indicated in broken lines in FIG. 2. Theroll R is prevented from following the axial extraction movement by thepresence of the side pieces 61.

When the extraction of the two portions M1, M2 of spindle is complete,the roll is no longer held between the two side pieces 61 and cancontinue the movement of discharge under the force of gravity alone orby other auxiliary means, such as a system of drive belts, towardconveyer members which are not shown and which are of a known type.

The two portions M1, M2 of spindle extracted from the roll R are made toreturn toward the entry area of the rewinder by two lateral conveyerswhich, in the illustrated example, consist of simple inclined guidesurfaces 71, along which the portions M1 and M2 of spindle roll bygravity until they reach corresponding rotating distributors 73 locatedin the terminal areas of the guide surfaces 71. The portions M1, M2 ofthe winding spindles accumulate behind the rotating distributor 73which, for each of the guide surfaces 71, discharge the portions M1 orM2 of spindle individually toward a corresponding cradle 75 having aV-shaped cross section (see FIG. 3 in particular).

Each of the two cradles 75 is associated with a correspondinglongitudinal pusher 77 fixed to an actuator which consists, in theillustrated example, of a flexible member 79 driven by a correspondingmotor 81. When a corresponding portion M1 or M2 of spindle has beendischarged into the corresponding cradle 75, the two pushers 77 aredriven simultaneously to push the two portions M1 and M2 toward anintermediate cradle which constitutes the extension of the two cradles75 and which is formed by a central rotating distributor 83. Thesimultaneous movement of the two pushers 77 toward the rotatingdistributor 83 not only causes the portions M1 and M2 of spindle to bedischarged onto the cradle formed by the central rotating distributor83, but also causes them to be connected axially at the surfaces S1 andS2, so that the complete winding spindle is reconstituted on the cradleformed by the rotating distributor 83. The rotation of the centraldistributor 83 then causes the discharge of the winding spindle M,reassembled in this way, on the central runway 13 toward the conveyer 11which returns the spindle to the winding area.

To prevent the accidental disconnection of the portions M1 and M2 ofspindle along the path from the central distributor 83 to the windingarea delimited by the roll 1 and the curved surface 7, it is possible tohave the spindle path delimited laterally by retaining side pieces whichprevent axial movements of the portions M1 and M2.

The winding takes place preferably (as described above) directly ontothe extractable spindle. However, there is no reason why a tubular coreshould not be threaded onto the two portions of the spindle which havebeen connected together, and the web material wound onto the tubularcore which subsequently remains integral with the roll, while thespindle is extracted from the tubular core. In this case, the finishedproduct will consist of turns of web material wound on a tubular corewhose thickness and density may be less than those of the conventionaltubular cores used for this purpose. However, the first possibility(with winding directly onto the spindle) is preferable, since it enablesrolls with axial holes but without tubular cores to be produced.

FIG. 5 shows a schematic plan view of the layout of the machine, inwhich the number 100 indicates an unwinder of parent rolls and 101indicates a gluing machine for gluing the rolls supplied by the rewinderwhich is indicated in a general way by 105. The two extraction means areindicated by 25A and 25B.

It is to be understood that the drawing shows only an example providedsolely as a practical demonstration of the invention, and that thisinvention may be varied in its forms and dispositions without departurefrom the guiding concept of the invention. Any reference numbers presentin the attached claims have the purpose of facilitating the reading ofthe claims with reference to the description and to the drawing, and donot limit the scope of protection represented by the claims.

What is claimed is:
 1. A peripheral rewinding machine for producingrolls of wound web material, comprising an insertion device forsequentially inserting winding spindles into a winding area; windingmeans in said winding area, which wind predetermined quantities of webmaterial onto said spindles to form said rolls; downstream of saidwinding area, an extractor for extracting said spindles from the rollsof web material formed thereon; a recirculation path for returning thespindles extracted from said rolls toward said insertion device; whereineach of said spindles is present in two portions which can be connectedand disconnected, said extractor extracts each of said two portions froma corresponding end of a corresponding wound roll, and means areprovided for reconnecting said two portions to each other before saidspindles are reinserted into said winding area, said means forreconnecting being arranged along said recirculation path.
 2. Themachine as claimed in claim 1, wherein said extractor is associated withtwo conveyers which extend laterally with respect to the winding area,to return the two portions of each spindle separately toward saidinsertion device, said means for reconnecting the two portions of saidspindles to each other being located before the winding area.
 3. Themachine as claimed in claim 2, wherein said conveyers comprise runwaysfor recirculating the two portions of said spindles.
 4. The machine asclaimed in claim 1, wherein said means for reconnecting the two portionsof said spindles connect said two portions before the spindles arereturned toward the insertion device.
 5. The machine as claimed in claim1, 2, 3 or 4, wherein said two portions of each spindle have, at theends to be connected, complementary conical surfaces.
 6. The machine asclaimed in claim 1, 2, 3 or 4, wherein said means for reconnecting thetwo portions of each spindle to each other comprise longitudinal guidemembers for the two portions to be connected and axial pushing memberswhich push said two portions toward each other.
 7. A method forproducing rolls of web material, comprising: inserting a winding spindleinto a winding area; winding a predetermined quantity of web material onsaid winding spindle to form a roll around said winding spindle;discharging said roll from said winding area; and thereafter extractingsaid winding spindle from the roll; wherein said spindle is present intwo portions, said two portions are connected before introducing saidspindle into said winding area, and the two portions of a spindle areextracted separately from opposite ends of the roll after the roll hasbeen discharged from the winding area.
 8. The method as claimed in claim7, wherein said two portions of said spindle are separately conveyedfrom an extractor which extracts said two portions from said roll towardan insertion device, and are connected to one another before saidinsertion device introduces said spindle into said winding area.
 9. Themethod as claimed in claim 7, wherein said two portions of said spindleare reconnected to one another after having been extracted from saidroll and the spindle formed by said two reconnected portions is returnedtoward an insertion device for insertion into said winding area.
 10. Aperipheral rewinding machine for producing rolls of wound web material,comprising an insertion device for sequentially inserting windingspindles into a winding area; winding means in said winding area, whichwind predetermined quantities of web material onto said spindles to formsaid rolls; downstream of said winding area, an extractor for extractingsaid spindles from the rolls of web material formed thereon; arecirculation path for returning the spindles extracted from said rollstoward said insertion device; wherein each of said spindles is presentin two portions which can be connected and disconnected, said extractorextracts each of said two portions from a corresponding end of acorresponding wound roll, and means are provided for reconnecting saidtwo portions to each other before said spindles are reinserted into saidwinding area, wherein said means for reconnecting the two portions ofeach spindle to each other comprise longitudinal guide members for thetwo portions to be connected and axial pushing members which push saidtwo portions toward each other and wherein said axial pushing memberscomprise an intermediate rotating distributor on which said two portionsare connected together, the distributor discharging the connectedspindles toward the insertion device.
 11. The machine as claimed inclaim 10, wherein said extractor is associated with two conveyers whichextend laterally with respect to the winding area, to return the twoportions of each spindle separately toward said insertion device, saidmeans for reconnecting the two portions of said spindles to each otherbeing located before the winding area.
 12. The machine as claimed inclaim 11, wherein said conveyers comprise runways for recirculating thetwo portions of said spindles.
 13. The machine as claimed in claim 10,wherein said means for reconnecting the two portions of said spindlesconnect said two portions before the spindles are returned toward theinsertion device.